1. Technical Field
The present disclosure relates to bolus tracking and, more specifically, to a system and method for automatic trigger-ROI detection and monitoring during bolus tracking.
2. Discussion of Related Art
Bolus tracking is used as part of some medical imaging procedures such as computed tomography (CT) angiography or magnetic resonance imaging (MRI) angiography for visualizing blood vessels and organs within the human body. During bolus tracking for CT angiography, a quantity of radio-opaque contrast media known as a bolus is injected into a patient's circulatory system via a peripheral intravenous cannula. The radio-opaque contrast media may then be imaged using a computed tomography (CT) scanner and the volume of the bolus may be observed. A triggering region of interest (trigger-ROI) is defined within the body and the CT scanner may be used to detect when the contrast arrives at the trigger-ROI. This is achieved by using a series of dynamic low-dose monitoring scans. Then, after sufficient time elapses to allow the bolus to travel from the trigger-ROI to a predetermined volume of interest (VOI), the predetermined VOI is imaged. By examining the appearance and volume of the bolus within the VOI, significant diagnostic information pertaining to the visualized blood vessels may be obtained.
Bolus tracking is used to image blood flow through arteries such as the carotid arteries, coronary artery, through highly vascularized organs such as the liver, or other regions through which blood flows.
Generally, the location of the monitoring scan and the placement of the trigger-ROI are defined manually by the technician performing the study. The contrast arrival is detected either visually by the technician or with the assistance of software which alerts the technician when the intensity inside the ROI has increased by more than a pre-set threshold.